package com.hu.juc.day02.T2;

import java.util.concurrent.CountDownLatch;

/**
 * CountDownLatch主要有两个方法，当一个或多个线程调用await方法时，这些线程会阻塞。
 * 其它线程调用countDown方法会将计数器减 1(调用countDown方法的线程不会阻塞),
 * 当计数器的值变为 0时，因await方法阻塞的线程会被唤醒，继续执行。
 */
public class CountDownLatchDemo {
    public static void main(String[] args) throws InterruptedException {
        CountDownLatch countDownLatch = new CountDownLatch(6);
        for (int i = 1; i <= 6; i++) {
            new Thread(() -> {
                System.out.println(Thread.currentThread().getName() + "\t离开教室");
                countDownLatch.countDown();
            }, String.valueOf(i)).start();
        }
        countDownLatch.await();
        System.out.println(Thread.currentThread().getName() + "\t班长关门");
    }

    private static void CloseDoor() {
        for (int i = 1; i <= 6; i++) {
            new Thread(() -> {
                System.out.println(Thread.currentThread().getName() + "\t离开教室");
            }, String.valueOf(i)).start();
        }
        System.out.println(Thread.currentThread().getName() + "\t班长关门");
    }
}
